\documentclass{article}

\usepackage{agda}

\pagestyle{empty}

\begin{document}

\noindent Text.
\AgdaHide{
\begin{code}%
%
\>[2]\AgdaKeyword{mutual}\<%
\end{code}}
\begin{code}%
\>[2][@{}l@{\AgdaIndent{1}}]%
\>[4]\AgdaKeyword{postulate}\AgdaSpace{}%
\AgdaPostulate{A}\AgdaSpace{}%
\AgdaSymbol{:}\AgdaSpace{}%
\AgdaPrimitiveType{Set}\<%
\end{code}
More text.
\begin{AgdaMultiCode}
\begin{code}%
%
\>[2]\AgdaKeyword{mutual}\<%
\end{code}
\begin{code}%
\>[2][@{}l@{\AgdaIndent{1}}]%
\>[4]\AgdaKeyword{postulate}\AgdaSpace{}%
\AgdaPostulate{B}\AgdaSpace{}%
\AgdaSymbol{:}\AgdaSpace{}%
\AgdaPrimitiveType{Set}\<%
\end{code}
\end{AgdaMultiCode}
Even more text.

\end{document}